Pickproof lock cylinder

ABSTRACT

A lockset for installation on a door panel is accessible from the outside as well as from the inside of the door. An outside keyway in a cylinder plug receives a key to turn the plug in a cylinder housing and so actuate the lockset. An inside manual control moves a blocking device from a free position permitting the plug to turn into a blocking position preventing the plug from turning. The blocking device may be a ball moved into and held in a blocking position engaging both the plug and the housing. When not held, the ball stays or is moved out of blocking position upon relative rotation of the plug and housing.

[ Jan. 1,1974

[ PICKPROOF LOCK CYLINDER [75] Inventor: Ernest L. Schlage, Burlingame,

Calif.

[73] Assignee: Schlage Lock Company, San

Francisco, Calif.

22 Filed: May 1, 1972 21 Appl. No.: 248,962

[52] US. Cl. 70/362, 70/364 A [S 1] Int. Cl E05b 27/00 [58] Field of Search 70/364 A, 364 R,

Kuchler 70/14 C DeVines 70/364 A Primary ExaminerRobert L. Wolfe AtlomeyMarcus Lothrop et al.

[57] ABSTRACT A lockset for installation on a door panel is accessible from the outside as well as from the inside of the door. An outside keyway in a cylinder plug receives a key to turn the plug in a cylinder housing and so actuate the lockset. An inside manual control moves a blocking device from a free position permitting the plug to turn into a blocking position preventing the plug from turning. The blocking device may be a ball moved into and held in a blocking position engaging both the plug and the housing When not held, the ball stays or is moved [56] References Cited UNITED STATES PATENTS out of blocking position upon relative rotation of the plug and housing. 3,670,538 6/1972 Curry 70/271 1,918,719 7/1939 Schlage 70/14 C 22 Claims, 14 Drawing Figures PATENTEDJM NW N 3,782,143

- SHEET 1 [IF 3 PATENTEU JAN 1 I974 SHEEI20F3 PICKPROOF LOCK CYLINDER Patents related to the present disclosure are U.S. Pat. No. 1,918,719 issued July 18, 1933 to Walter R. Schlage and U.S. Pat. No. 3,128,618 issued Apr. 14, 1964 to Hollis L. DeVines, both assigned to the assignee hereof.

Many locksets, particularly those installed in door panels in buildings, depend for their outside security on the provision of a cylinder housing fixed in the lockset and containing a cylinder plug rotatable within the housing. The plug is accessible from the outside of the door panel and contains a keyway. Insertion of a key into the keyway displaces a number of spring pressed tumbler pins movably arranged within the cylinder housing and within the cylinder plug. When a proper key is introduced into the keyway and turned, the plug is rotated within the cylinder and the lockset is correspondingly actuated.

The lockset is sometimes provided on the inside with a manual control effective to permit or to preclude the full introduction of a key into the keyway. When the key is so shut out, the lockset cannot be actuated by any usual key. To cope with emergency situations, a special key can always be inserted into the keyway and overcome the inhibition of the interior manual control and actuate the lockset.

Unauthorized persons can use lock picking tools or apparatus from the outside of the lockset and by adroit manipulation of the pin tumbler mechanism can gain access to the interior.

It is therefore an object of my invention to provide a pickproof lock cylinder arranged so that the lockset cannot be actuated from the outside, even though it is picked or even by a regular or even a special emergency key.

Another object of the invention is to provide a pickproof lock cylinder that can be controlled from the inside of the door, so that the lockset can easily be rendered completely pickproof or normally accessible.

Another object of the invention is to provide a pickprooflock cylinder that, when set, cannot be operated, short of destruction of the lockset.

Another object of the invention is to provide a pickproof lock cylinder which can readily be utilized in locksets already existing and is compatible with present lockset construction, manufacturing techniques and requirements.

Another object of the invention is to provide a pickproof lock cylinder which even though picked will not actuate the lockset.

A further object of the invention is in general to provide an improved pickproof lock cylinder.

Other objects together with the foregoing are attained in the embodiments of the invention described in the accompanying description and illustrated in the accompanying drawings, in which:

FIG. I is a view from above, some parts being in cross-section on a horizontal plane and some parts being broken away, showing a pickproof lock cylinder installed in a lockset mounted on a door panel;

FIG. 2 is a cross-section on a horizontal, axial plane through a lock cylinder pursuant to the invention in free position;

FIG. 3 is a view similar to FIG. 2 but with the mechanism in blocked position;

FIG. 4 is a cross-section, the plane of which is indicated by the line 4-4 of FIG. 2;

FIG. 5 is a cross-section, the plane of which is indicated by the line 5-5 of FIG. 3;

FIG. 6 is a view similar to FIG. 2 but showing a modified form of pickproof lock cylinder pursuant to the invention in free position;

FIG. 7 is a view comparable to FIG. 6 but showing the parts in blocked position;

FIG. 8 is a cross-section, the plane of which is indicated by the line 88 of FIG. 7;

FIG. 9 is a cross-section on a vertical, axial plane through a lock cylinder embodying a variant form of the invention and shown in free position;

FIG. 10 is a cross-section on a horizontal, axial plane through a further modified form of pickproof lock cylinder pursuant to the invention, shown in free position;

FIG. 11 is a view comparable to FIG. 10 but with the parts in blocked position;

FIG. 12 is a cross-section, the plane of which is indicated by the line 1212 of FIG. 10;

FIG. 13 is a cross-section, the plane of which is indicated by the line 13l3 of FIG. 11; and

FIG. 14 is a fragmentary side elevation of the structure of FIG. 10 in free position.

In a representative installation there is provided a lock-set 6 mounted on a door panel 7 designed to swing with respect to a frame 8. The lockset includes and actuates a bolt such as a latch bolt 9 so that the door can be secured or can be swung toward the inside 11 from the outside 12. On the outside of the lockset there is provided an operator 13 such as a knob, and on the inside a somewhat similar operator 14 is provided. The knob 14 is particularly equipped with a manual control 16. See U.S. Pat. No. 1,918,719.

There is incorporated in the lockset, preferably in the outside knob 13, a lock cylinder mechanism 18 of the usual sort having an exterior, generally cylindrical housing 19 and having a central, circular cylindrical bore 21 symmetrical about a longitudinal axis 22. A cylinder plug 23 is designed to rotate in the bore 21 and has an enlarged flange 24 at one end abutting against the end of the housing 19. A removable collar 26 at the other end of the plug 23 engages the housing. The flange and collar maintain the axial position of the plug within the housing.

The plug is pierced by a keyway 27 extending along the axis 22. An appropriate key, not shown, when disposed in the keyway actuates a number of tumbler pins 28 (FIG. 9) in the customary way. Absent a proper key, the pins are ordinarily forced into locking position by springs 31. In this position the parting line 32 between adjacent tumblers does not coincide with the shear line or plane coincident with the circular cylindrical wall of the bore 21. That is, one or more of the pins 28 straddles the shear line, being partly engaged in the plug and partly engaged in the housing. The plug cannot then turn in the housing to actuate the lockset. When an appropriate key is inserted, the pins 28 are thereby rearranged so that the parting surfaces 32 of all of them coincide with the shear line. Rotation of the key then produces an accompanying rotation of the plug. Also produced is a simultaneous rotation of a driver bar 33 captured in the cap 26 so that it necessarily rotates with the plug. The driver bar 33 is connected by standard mechanism, not shown, to actuate the bolt 9. A person with an authorized key inserted into the plug can rotate the plug and gain access from the outside to the inside.

A person unauthorized and without a key by utilizing lock picks can manipulate the various tumbler pins 28 in such a fashion that all of the parting surfaces 32 are properly lined up, as though with a key, as previously described, and can so gain access from the outside to the inside.

In accordance with the present invention, I provide means for precluding such unauthorized operation of the lockset. To that end, as particularly shown in FIG. 2, I provide in the plug 23, at a convenient location near to but separate from the keyway 27, a cross or radial passage 36 and an intersecting longitudinal passage 37 extending through the plug. Meeting with the passage 36 in one relatively rotated position of the plug in the housing is a smaller passage 38 in the housing. Carried by the plug and disposed in the passage 36 is a blocking member. For example, this is a hardened ball 39. In one free position, as shown in FIG. 2, the ball is entirely contained within the plug and rests against the bottom of a notch 41 having inclined or cammed sides 42 and 43 and cut into a rod 44 disposed to slide freely in the passage 37. One end of the rod beyond the passage is secured firmly to a cross plate 46 movable axially within the cap 26 between the end thereof and the end of the plug. The plate extends transversely and has its ends guided in slots 47 and 48 cut diametrically across the end of the plug, so that the plug and the plate necessarily rotate together. The plate is also secured to a driver bar 49 that correspondingly turns with the plug and is effective to actuate the bolt 9.

When it is desired to preclude the operation of the lock cylinder by any means, including keys and picking tools, the manual control 16 on the inside is depressed. It may be retained in depressed position by standard means. This moves a central stem 51 accordingly and axially translates the driver bar 49, the plate 46 and the rod 44. The result of this translation is that the cam incline 42 forces the blocking member or ball 39 partly out of its position entirely within the plug and forces the ball partly into the somewhat smaller opening 38 in the housing. This is a non-wedging engagement. Since the rod notch 41 moves entirely past the ball 39 when it is so lodged, as shown in FIG. 3, the ball is firmly held in blocking position by the solid rod 44 and against dislodgment by any means. Further, since the ball lies across the clearance space between the plug and the housing, it is impossible for the plug to be rotated in the housing by any means. The lockset cannot then be actuated. Preferably, the length of the rod 44 is such that while normally and in free or unblocking location it is well within the passage 37, it does project beyond the end of the plug when it is in blocking position. The rod projection affords a visual and tactile indication that no rotation of the plug in the casing is possible.

When a person on the inside decides to free the lock cylinder, he simply restores the manual control 16 to the relaxed or projected position shown in FIG. 1. This permits the rod 44 to be restored to its free position. To that end the plate 46 likewise carries a plunger 52 movable in a bore 53 in the plug alongside the keyway and containing a restoring spring 54. When the control 16 is released, all ofthe parts connected to the plate 46 are restored to their initial positions. The ball or blocking means 39 may still be partly within the small passage 38 in the housing. The relationship of the diameter of the passage 38 to the diameter of the ball is such that the ball does not at any time wedge into the opening 38.

Rather, when the rod 44 is withdrawn, the ball can be cammed out of blocking position upon the initial rotation of the plug with respect to the housing. The edge of the opening 38 presses against the inclined surface of the ball and restores the ball approximately to the position shown in FIG. 2 from the position shown in FIG. 3.

It is sometimes desired to provide, in addition to the pickproof arrangement, a key shut-out feature as well. In that instance the arrangement shown in FIGS. 6-9 is employed. The rod 44 is provided not only with the notch 41 in a slightly different location than before, but also has a notch 61 designed to engage and, by camming, to displace laterally a second ball 62. This ball normally is outside of the keyway 27 but when displaced projects into the keyway, as shown in FIG. 7, and, being backed by the displaced rod 44, is effective to prevent more than the initial entrance of the usual key into the keyway. A specially grooved key may be made to enter the keyway as shown in the DeVines patent, above, but the ball 39 still prevents plug rotation, so even a special key is not effective. With this arrangement there is not only provided an absolute bar to the rotation of the plug in the housing, but even the entry of the usual keys and of most picking tools into the keyway is precluded.

Should it be preferred not to afford an exterior indication of the condition of the lock cylinder, the rod 44 is made shorter and is operated in a passage 63 which is entirely comparable to the passage 37 except that it does not open onto the exterior of the plug flange 24.

An effective and simplified version of the blocking lock cylinder is afforded as shown in FIG. 9. At least one of the key actuated tumbler pins 28 is utilized as the blocking means to preclude rotation of the plug in the housing. In this instance the plate 46 at the end of the driver bar 33 is provided with an eccentric pin 67 axially movable to and fro in a special passage 68 in the plug alongside the keyway 27. One of the regular tumbler pins 28 is replaced by a similar but special tumbler pin 69. This is like the other tumbler pins 28 except that it has a circumferential groove 71 entirely around it. In one position, with the key absent, the tumbler pin groove 71 registers exactly with the passage 68 and holds an associated pin 28 straddling the shear surface between the plug and the housing.

In the position of the parts shown in FIG. 9 with the manual control 16 relaxed, the tumbler pins, including the pin 69, are all positioned and key actuated in the normal fashion, as described hereinabove. However, when the manual control 16 is depressed, the driver bar 33 is translated to the left in FIG. 9 and the plate 46 moves the blocking means; i.e., the pin 67, through the passage 68 and into the groove 71. The pin 69 cannot thereafter be moved and the adjacent pin 28 retains its straddling position. The blocking means thus is effective to preclude rotation of the plug within the housing. The pin 67 is readily withdrawn with the driver bar 33 when the control 16 is released. The pin 69 is freed to operate with the remaining tumbler pins 28 as usual.

As a further modification of an appropriate pickproof lock cylinder, there is shown in FIGS. 10-13 an arrangement in which many of the parts are exactly as before. The plate 46, however, becomes a plate 76 at the end of the driver bar 49 and has extended lugs 78 and 79. In one position of axial displacement, the lugs not only occupy the usual notches 47 and 48 in the plug, but also move into opposite notches 81 and 82 in the housing. The plate 76 carries a rod 83 movable in a blind passage 84 within the plug 86, and a comparable rod 87 moves in a similar bore 88 in the plug against the urgency of a spring 89 therein.

In this arrangement, the depression of the manual control 16 translates the driver bar 49 from the free position shown in FIG. and into the blocking position shown in FIG. ll, wherein the plate lugs '78 and 79 in engagement with the plug are likewise brought into engagement with the walls of the housing notches 81 and 82. No rotation between the plug and the housing can then occur. When the lockset is freed by release of the manual control, then the driver bar 49 and the plate 76 with its lugs 78 and 79 are translated by the spring 89 to free the lugs from the housing. The plug can then be rotated therein as usual.

To preclude release of the lockset by translation of the plate 76 by a tool inserted through the keyway from outside, it is preferably arranged that the portion of the plate in alignment with the keyway be cut away, leaving a notch M (FIG. 113). With this arrangement, a special key or a long tool inserted into the keyway cannot engage the cross plate 46 and so cannot displace it inwardly to release the blocked lock cylinder.

in all forms of the arrangement there is a means subject to manual control from the inside for blocking or binding the normally rotary plug to the containing housing. No key or tool inserted into the keyway can produce any plug rotation and so cannot operate the lockset even though the tumbler pins might be picked or arranged in their proper plug freeing positions.

What is claimed is:

l. A pickproof lock cylinder for a lockset having a keyway and a driver bar movable relative to said keyway comprising a cylinder housing adapted to be fixed in said lockset, a cylinder plug containing said keyway and rotatable within said housing, a blocking device, means for mounting said blocking device for movement between a blocking position in interengagement with both said housing and said plug and a free position out of interengagement with both said housing and said plug, and means responsive to said movement of said driver bar for moving said blocking device into said blocking position.

2. A deviceas in claim 1 in which said mounting means includes a passage within said housing and a passage within said plug adapted to align with each other in one rotary position of said plug in said housing.

3. A device as in claim 2 in which one of said passages is smaller than the other of said passages.

4. A device as in claim 2 in which said blocking device is freely movable in one of said passages and is only partly receivable in the other of said passages.

5. A device as in claim 3 in which said blocking device is freely movable in the larger of said passages and is only partly receivable in the smaller of said passages.

6. A device as in claim 5 in which said blocking device makes non-wedging engagement with the smaller of said passages.

7. A device as in claim 1 in which said blocking device is a ball.

8. A device as in claim 3 in which the smaller of said passages is within said housing.

9. A device as in claim 1 including a rod engageable with said blocking device and mounted in and movable axially with respect to said plug by said driver bar control.

10. A device as in claim 9 including a spring for urging said rod in one axial direction in said plug.

111. A pickproof lock cylinder for a lockset having a keyway and a driver bar control independent of said keyway comprising a cylinder housing having a bore concentric with an axis, a cylinder plug containing said keyway and disposed in said bore for rotation about said axis, means for preventing axial motion of said plug in said housing, means defining an axially extending passage in said plug, a rod axially movable in said passage between a free position and a blocking position, means for translating operation of said driver bar control into axial movement of said rod, a blocking device movable between a blocking position precluding rotation of said plug about said axis and a free position permitting rotation of said plug about said axis, and means responsive to movement of said rod from said free position to said blocking position for moving said blocking device into said blocking position.

12. A device as in claim 11 including means on said rod for holding said blocking device in said blocking position when said rod is in said blocking position.

13. A device as in claim 11 including means for moving said blocking device out of said blocking position when said rod is in said free position.

14. A device as in claim 13 in which said moving means is responsive to relative rotation between said plug and said housing.

15. A device as in claim 11 in which said manual control includes means movable along said axis relative to said plug, said passage is disposed alongside said axis, and transversely extending means transmit axial motion of said manual control means to said rod.

16. A device as in claim 11 including a spring for urging said rod toward said free position.

17. A device as in claim 1 l in which said blocking device is movable between blocking position and free position by relative rotation of said plug and said housing.

118. A device as in claim 17 in which said blocking device is so moved by a camming action.

19. A device as in claim 17 in which said blocking device is a ball.

20. A device as in claim 11 in which said passage opens through both the inner end and the outer end of said plug, and part of said rod in said blocking position lies beyond said outer end and in said free position lies within said outer end.

21. A pickproof lock cylinder for a lockset adapted to be installed on a door panel, said lockset including an inside operator, including a driver bar control associated with said inside operator, and including an outside cylinder housing with a cylinder plug rotatable therein, blocking means movable into and out of a blocking position engaging said cylinder housing and said cylinder plug and preventing rotation of said plug in said housing, and means for connecting said control to move said blocking means into said blocking position.

22. In a lock cylinder having a cylinder housing and a cylinder plug rotatable therein, said cylinder plug including a keyway, a blocking device adapted to be moved into and out of a blocking position engaging said cylinder plug and said cylinder housing and precluding rotation of said cylinder plug in said cylinder housing, and means including a driver bar independent of said keyway for moving said blocking means into said blocking position. 

1. A pickproof lock cylinder for a lockset having a keyway and a driver bar movable relative to said keyway comprising a cylinder housing adapted to be fixed in said lockset, a cylinder plug containing said keyway and rotatable within said housing, a blocking device, means for mounting said blocking device for movement between a blocking position in interengagement with both said housing and said plug and a free position out of interengagement with both said housing and said plug, and means responsive to said movement of said driver bar for moving said blocking device into said blocking position.
 2. A device as in claim 1 in which said mounting means includes a passage within said housing and a passage within said plug adapted to align with each other in one rotary position of said plug in said housing.
 3. A device as in claim 2 in which one of said passages is smaller than the other of said passages.
 4. A device as in claim 2 in which said blocking device is freely movable in one of said passages and is only partly receivable in the other of said passages.
 5. A device as in claim 3 in which said blocking device is freely movable in the larger of said passages and is only partly receivable in the smaller of said passages.
 6. A device as in claim 5 in which said blocking device makes non-wedging engagement with the smaller of said passages.
 7. A device as in claim 1 in which said blocking device is a ball.
 8. A device as in claim 3 in which the smaller of said passages is within said housing.
 9. A device as in claim 1 including a rod engageable with said blocking device and mounted in and movable axially with respect to said plug by said driver bar control.
 10. A device as in claim 9 including a spring for urging said rod in one axial direction in said plug.
 11. A pickproof lock cylinder for a lockset having a keyway and a driver bar control independent of said keyway comprising a cylinder housing having a bore concentric with an axis, a cylinder plug containing said keyway and disposed in said bore for rotation about said axis, means for preventing axial motion of said plug in said housing, means defining an axially extending passage in said plug, a rod axially movable in said passage between a free position and a blocking position, means for translating operation of said driver bar control into axial movement of said rod, a blocking device movable between a blocking position precluding rotation of said plug about said axis and a free position permitting rotation of said plug about said axis, and means responsive to movement of said rod from said free position to said blocking position for moving said blocking device into said blocking position.
 12. A device as in claim 11 including means on said rod for holding said blocking device in said blocking position when said rod is in said blocking position.
 13. A device as in claim 11 including means for moving said blocking device out of said blocking position when said rod is in said free position.
 14. A device as in claim 13 in which said moving means is responsive to relative rotation between said plug and said housing.
 15. A device as in claim 11 in which said manual control includes means movable along said axis relative to said plug, said passage is disposed alongside said axis, and transversely extending means transmit axial motion of said manual control means to said rod.
 16. A device as in claim 11 including a spring for urging said rod toward said free position.
 17. A device as in claim 11 in which said blocking device is movable between blocking position and free position by relative rotation of said plug and said housing.
 18. A device as in claim 17 in which said blocking device is so moved by a camming action.
 19. A device as in claim 17 in which said blocking device is a ball.
 20. A device as in claim 11 in which said passage opens through both the inner end and the outer end of said plug, and part of said rod in said blocking position lies beyond said outer end and in said free position lies within said outer end.
 21. A pickproof lock cylinder for a lockset adapted to be installed on a door panel, said lockset including an inside operator, including a driver bar control associated with said inside operator, and including an outside cylinder housing with a cylinder plug rotatable therein, blocking means movable into and out of a blocking position engaging said cylinder housing and said cylinder plug and preventing rotation of said plug in said housing, and means for connecting said control to move said blocking means into said blocking position.
 22. In a lock cylinder having a cylinder housing and a cylinder plug rotatable therein, said cylinder plug including a keyway, a blocking device adapted to be moved into and out of a blocking position engaging said cylinder plug and said cylinder housing and precluding rotation of said cylinder plug in said cylinder housing, and means including a driver bar independent of said keyway for moving said blocking means into said blocking position. 